Optimal level of positive end-expiratory pressure during nasal continuous airway pressure for severe bronchiolitis: a prospective study

Background: Nasal continuous positive airway pressure (nCPAP) has been increasingly applied in the pediatric setting. However, there is no uniform standard for setting and titrating positive end-expiratory pressure (PEEP) level, which is paramount to the effectiveness of the treatment. This study aimed to investigate the optimal parameters for nCPAP in the treatment of severe bronchiolitis based on clinical efficacy and pulmonary function parameters. Methods: A before-after prospective study was conducted with a total of 152 study subjects. These 152 hospitalized patients with severe bronchiolitis were treated and observed from December 2018 to February 2019. Comparisons were made between subjects for clinical symptoms, oxygenation improvement, correction of CO2 retention, degree of airway obstruction and respiratory mechanics improvement between three different positive end-expiratory pressure levels (PEEP). Results: nCPAP could effectively improve the clinical manifestations, blood gas analysis, pulmonary function and respiratory muscle energy consumption. The m-WCAS score, PaCO2, TPTEF/TE, VPEF/VE, respiratory system compliance (Crs) and resistance (Rrs) were significantly different at different PEEP levels (P<0.05). Although there were no hemodynamic changes at peep parameter levels in the three groups. Group 2 (PEEP: 6 cmH(2)O) had optimal clinical effects, and improvement in airway obstruction and respiratory mechanics compared with the group 1 (PEEP: 4 cmH(2)O) and the group 3 (PEEP: 7 cmH(2)O). Conclusions: PEEP of 6 cmH(2)O via nCPAP is considered as the optimal level in the treatment of infants with severe bronchiolitis.